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A Rodriguez

Publications and source records attributed to A Rodriguez.

At least 181 records · Page 10Linked to original sources
PubMed1995

Meta-analysis of randomised trials comparing coronary angioplasty with bypass surgery.

A patient with severe angina will often be eligible for either angioplasty (PTCA) or bypass surgery (CABG). Results from eight published randomised trials have been combined in a collaborative meta-analysis of 3371 patients (1661 CABG, 1710 PTCA) with a mean follow-up of 2.7 years. The total deaths in the CABG and PTCA groups were 73 and 79, respectively, with a relative risk (RR) of 1.08 (95% CI 0.79-1.50). The combined endpoint of cardiac death and non-fatal myocardial infarction occurred in 169 PTCA patients and 154 CABG patients (RR 1.10 [0.89-1.37]). Amongst patients randomised to PTCA 17.8% required additional CABG within a year, while in subsequent years the need for additional CABG was around 2% per annum. The rate of additional non-randomised interventions (PTCA and/or CABG) in the first year of follow-up was 33.7% and 3.3% in patients randomised to PTCA and CABG, respectively. The prevalence of angina after one year was considerably higher in the PTCA group (RR 1.56 [1.30-1.88]) but at 3 years this difference had attenuated (RR 1.22 [0.99-1.54]). Overall there was substantial similarity in outcome across the trials. Separate analyses for the 732 single-vessel and 2639 multivessel disease patients were largely compatible, though the rates of mortality, additional intervention, and prevalent angina were slightly lower in single vessel disease. The combined evidence comparing PTCA with CABG shows no difference in prognosis between these two initial revascularisation strategies. However, the treatments differ markedly in the subsequent requirement for additional revascularisation procedures and in the relief of angina. These results will influence the choice of revascularisation procedure in future patients with angina.

Angina Pectoris↗
PubMed1995

Resistance to herpes stromal keratitis conferred by an IgG2a-derived peptide.

Not all peripheral tissue antigens enter the thymus and it is unclear how the immune system remains tolerant to this class of self antigen. As tolerance to self peptides can generate gaps in the T-cell repertoire for cross-reactive foreign antigens, we investigated whether this mechanism might also diminish autoimmune reactions to similar peptides expressed by peripheral tissues. Herpes stromal keratitis (HSK) is a virally induced autoimmune reaction against corneal tissues mediated by T cells, and is a leading cause of human blindness. Resistance to HSK in mice is associated with allotypic variation in immunoglobulin genes, possibly because circulating immunoglobin-derived peptides can cross-tolerize T cells specific for corneal tissue autoantigens. Here we show that HSK is mediated by T-cell clones specific for corneal self antigens which also recognize an allotype-bearing peptide derived from IgG2a, and that exposure of HSK-susceptible mice to a soluble form of this peptide confers resistance to HSK. Shared expression of peptide subsequences between sequestered tissue proteins and circulating proteins may be important for maintenance of self-tolerance and prevention of autoimmunity.

Animals↗
PubMed1995

Recurrence rate of herpetic uveitis in patients on long-term oral acyclovir.

We examined the recurrence rate of herpetic uveitis (HU) in 13 patients (group A) treated prophylactically with long-term systemic acyclovir (600-800 mg/day) and compared it with that of 7 patients with no prophylactic therapy (group B). HU was diagnosed on the basis of a history of dendritic or disciform keratitis accompanied by iridocyclitis and iris atrophy. The study population consisted of 12 men and 8 women with a mean age at onset of uveitis of 52.9 years (range 19-78 years). All patients were followed for at least 8 months. The mean follow-up time of patients on long-term oral acyclovir was 26.0 months. In this group, only one patient experienced a single recurrent episode of uveitis while on 600-800 mg/day of acyclovir therapy; two additional patients had recurrence of HU within 16.2 months after the acyclovir dose was tapered below 600 mg/day. In striking contrast, 16 recurrences occurred in the 7 patients of group B (p < 0.05). Of these, the initial recurrence occurred within an average of 4.3 months following cessation of therapy. There was a significant difference (p < 0.05) in the mean recurrence-free interval between patients in group A (24.6 months) and those in group B (3.4 months). Herpetic uveitis is a serious ocular disease in which recurrence of inflammation results in severe ocular complications. The long-term use of oral acyclovir may be of benefit in the prevention of recurrences, and hence may reduce the blinding complications of this disease. Efforts at completing a randomized, placebo-controlled trial on this matter by the Herpes Epithelial Disease Study Group were unsuccessful due to insufficient patient recruitment.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Optimal timing of granulocyte colony-stimulating factor (G-CSF) administration after bone marrow transplantation. A prospective randomized study.

The positive role of G-CSF in hastening the myeloid recovery of patients undergoing allogeneic bone marrow transplantation (ALLO-BMT) or autologous bone marrow transplantation (ABMT) has recently been established. Considerable knowledge about adequate doses and route of administration has been accumulated in the past few years. Nonetheless, the optimal time to start growth-factor administration remains undetermined. We have performed a stratified study according to the source of hematopoietic progenitors (ALLO-BMT or ABMT), underlying disease and its stage, and acute graft-versus-host disease (GVHD) prophylaxis regimen and randomized patients in two arms: group A, which started G-CSF on day 0 (36 patients), and group B, which started on day +7 post-BMT (39 patients). The same dose (5 micrograms/kg/day) and route of administration were employed in both groups. We found no significant differences in the time to reach an absolute neutrophil count (ANC) of 0.1, 0.5, and 1 x 10(9)/l and 50 x 10(9) platelets/l (medians: 10 and 11, 14.5 and 14, 17 and 16, 23 and 24 days, respectively, in groups A and B). We did not find differences in the days of fever or days on antibiotic treatment with less than 1 x 10(9)/l ANC, rate of bacteriemia, or days of hospitalization in both groups. In contrast, a considerable saving of G-CSF in B group was found (mean days of infusion in group A, 18, versus 11 in group B) (p < 0.0001). This is equivalent to a saving of 1120 $US per patient.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1995

Antithrombotic effects of peroxynitrite: inhibition and reversal of aggregation in human platelets.

The inhibition of platelet aggregation by peroxynitrite, a reactive oxygen species derived from the interaction of nitric oxide (NO) and superoxide, was examined in platelet-rich plasma. In this report, we have used a preparation of peroxynitrite that was free of H2O2 and MnO2. As such, peroxynitrite dose-dependently (50-200 microM) inhibited aggregation of human platelets stimulated by ADP (5 microM), collagen (0.5 microgram), thrombin (0.5U/microL) and U46619 (1 microM). In addition, peroxynitrite reversed platelet aggregation induced by collagen, ADP, and thrombin. Peroxynitrite, preincubated with platelet-poor plasma or albumin (7%) for 30 min, did not alter the inhibition of platelet aggregation. This suggested that the inhibitory action of peroxynitrite may be due to nitrosylation of proteins, which by themselves possess activity, rather than conversion to NO or NO donors. Furthermore, we show that peroxynitrite increased the cGMP level only at 200 microM concentrations, further suggesting that the action of peroxynitrite was not completely due to its conversion to NO or NO donors.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗
PubMed1995

The value of combined serum angiotensin-converting enzyme and gallium scan in diagnosing ocular sarcoidosis.

PURPOSE: To evaluate the role of combined serum angiotensin-converting enzyme (ACE) activity and whole-body gallium (67GA) scanning in diagnosing sarcoidosis in patients with features consistent with ocular sarcoidosis but with normal or equivocal chest radiographs. METHODS: Serum ACE levels and whole-body 67GA scans were obtained as part of the initial workup in 22 patients with active ocular inflammation and ultimately biopsy-proven sarcoidosis (sarcoid uveitis group). A second group consisting of 70 patients with active uveitis in whom sarcoidosis also was considered a diagnostic possibility also was studied. All 70 patients ultimately had a definitive diagnosis other than sarcoidosis (nonsarcoid uveitis). All patients in this group also had a serum ACE and whole-body 67GA scan performed as part of their initial investigations. RESULTS: All patients in the sarcoid uveitis group had either an elevated ACE level or an abnormal scan. In 16 of the 22 patients, results of both tests were abnormal. In no patient in the nonsarcoid uveitis group were results of both tests abnormal. The sensitivity of an elevated ACE in diagnosing sarcoidosis was 73% and the specificity was 83%. Using the combination of a positive 67GA scan and an elevated ACE, the specificity for diagnosis was 100% and the sensitivity was 73%. CONCLUSIONS: The combination of serum ACE level and whole-body 67GA scan increases the diagnostic specificity without affecting sensitivity in patients with clinically suspicious ocular sarcoidosis who have normal or equivocal chest radiographs.

Adolescent↗
PubMed1995

Systemic immunosuppressive therapy and the occurrence of malignancy in patients with ocular inflammatory disease.

PURPOSE: To compare the occurrence of malignancy in patients with severe ocular inflammatory disease treated with systemic corticosteroids alone or with systemic immunosuppressive drugs with or without systemic corticosteroids. METHODS: The clinical records of 543 patients with ocular inflammatory disease treated with systemic corticosteroids and/or immunosuppressive chemotherapy were reviewed in a retrospective cohort study. Characteristics of patients treated with corticosteroids alone were compared with characteristics of patients treated with immunosuppressive agents with or without preceding corticosteroid treatment. The rates of malignancy after initiation of drug therapy were compared using an exact test for incidence rate data. RESULTS: Compared with patients treated with corticosteroids alone, patients treated with immunosuppressants with or without corticosteroid treatment were older and had more severe systemic disease. During a total of 1261 person-years of follow-up, a malignancy developed in five patients. The rate of malignancy in the immunosuppressant group (4 malignancies during 968 person-years of follow-up) was not significantly different from the rate in the corticosteroids alone group (1 malignancy during 293 person-years of follow-up) (P > 0.90, exact test for incidence rate data). CONCLUSION: These findings do not support the hypothesis of an increased risk of malignancy in patients with severe ocular inflammatory disease who are treated with systemic immunosuppressive agents compared with patients treated with systemic corticosteroids.

Adult↗
PubMed1995

Increasing the diagnostic yield of conjunctival biopsy in patients with suspected ocular cicatricial pemphigoid.

BACKGROUND: Ocular cicatricial pemphigoid is a chronic, progressive, autoimmune disease that scars mucous membranes and may lead to blindness. It is of critical importance to be able to make the diagnosis as early as possible to allow early treatment. Conjunctival biopsy facilitates the early diagnosis of this condition. MATERIALS AND METHODS: Conjunctival biopsy results of 166 consecutive patients seen over a 7-year period, in whom the diagnosis of ocular cicatricial pemphigoid was considered, were reviewed. RESULTS: One hundred twenty-one patients ultimately received a diagnosis of ocular cicatricial pemphigoid. Immunofluorescence studies demonstrated characteristic deposition of immunoreactants at the epithelial basement membrane zone in 63 patients (sensitivity = 52%). When immunofluorescent-negative or inconclusive biopsies were processed further using an immunoperoxidase technique an additional 37 diagnoses were made. This represented an increase in sensitivity from 52% with immunofluorescence only to 83% with the addition of the immunoperoxidase technique. CONCLUSION: The routine use of the immunoperoxidase technique in immunofluorescent-negative biopsies, allied with appropriate harvesting and handling of biopsied conjunctiva, should significantly increase the diagnostic yield in patients with clinically suspect ocular cicatricial pemphigoid.

Adult↗
PubMed1995

Disease relapse in patients with ocular manifestations of Wegener granulomatosis.

PURPOSE: To evaluate possible factors associated with disease relapse in patients with ocular manifestations of Wegener granulomatosis. METHODS: Eight patients with ocular manifestations of Wegener granulomatosis were longitudinally followed for a mean period of 34 months. Serial antineutrophil cytoplasmic antibody (ANCA) levels were determined on all patients. RESULTS: All eight patients had either scleritis alone or scleritis combined with peripheral ulcerative keratitis. Clinical disease remission was achieved in all patients using immunosuppressive chemotherapy. Five patients had subsequent relapse after treatment withdrawal. The serum ANCA level had failed to revert to normal during remission in four of the five patients who had had relapses. The ANCA levels for all three patients who remained in remission without therapy converted to normal. There was no significant difference in the initial serum ANCA level (P = 0.35) or the mean cumulative cyclophosphamide dose (P = 0.13) between those who had a relapse and those who did not. CONCLUSION: Failure of ANCA titers to revert to normal levels may be associated with the potential for relapse in patients with ocular manifestations of Wegener granulomatosis.

Adult↗
PubMed1995

Falls and major injuries are risk factors for thoracolumbar fractures: cognitive impairment and multiple injuries impede the detection of back pain and tenderness.

Risk factors for thoracolumbar fracture (TLF) and occurrence of back pain/tenderness detection (BPTD) in TLF patients have not been fully evaluated. Of 4142 blunt trauma patients directly admitted to a level I trauma center, 183 (4.4%) had a TLF. Risk factors for TLF (p < or = 0.05) were major non-TLF injuries (Abbreviated Injury Scale score > or = 3) and a fall mechanism of injury. Of 110 with TLF, Glasgow Coma Scale score (GCS) of 13 to 15, and no myelopathy, 34 (30.9%) had no BPTD; 7 of 34 (20.6%) required operative spinal stabilization. BPTD was lacking in 63% of patients with GCS scores of 13 to 14 compared to 22% of patients with GCS scores of 15 (p = 0.001). BPTD was decreased when major non-TLF injuries were present (63 vs. 91%) in the GCS score of 15 group (0.003), but similar in GCS score of 13 to 14 patients. In patients with GCS scores of 13 to 15, decreased BPTD is simultaneously related to both cognitive dysfunction and major injuries (p = 0.005). In conclusion, major injuries and falls are risks for TLF and cognitive deficit and major injury impedes BPTD in TLF. Thoracolumbar x-ray films should be carefully considered in patients with altered mentation or major injury.

Accidental Falls↗
PubMed1995

Histological changes in the uterus during postpartum in the mare.

An histological study of the postpartum period in 29 mares was carried out. Uterine biopsies were taken daily during the first 10 days postpartum in a total of 87 samples. At day 0, equine endometrium was characterized in the surface by the presence of regularly ordered microcaruncles; the stratum spongiosum was oedematous and contained distended and scarce glands. Degenerative changes in microcaruncles and endometrial glands were present on day 1 postpartum. The epithelium of the microcaruncles from 2 to 5 days postpartum showed cytoplasmic vacuolization, karyorrhexis and an inflammatory reaction with neutrophils and phagocitic cells. On day 7 postpartum, the histology of the endometrium was similar to the normal proestrus with cuboidal luminal epithelium and an oedematous stromal tissue. The changes are usually completed within days 9 and 10 postpartum with the histologically typical appearance of estrus in mares.

Animals↗
PubMed1995

Immunocytochemical study of type IV collagen and laminin in canine mammary tumours.

We performed an immunohistochemical study of the basement membrane (BM) proteins laminin and type IV collagen in 35 canine mammary tumours, histologically classified according to the World Health Organization's suggested classification. Laminin and type IV collagen were seen in extracellular locations but only laminin was present in epithelial and myoepithelial cells and chondrocytes. The BM was always continuous in adenomas and fibroadenomas. In the 20 malignant tumours studied, the basement membrane was continuous in one, discontinuous in five, and virtually absent in 14. When present, the BM of malignant tumours varied in width and distribution in the same area. The benign and malignant mixed tumours did not have BM separating epithelial and newly-formed mesenchymal structures. In areas of abundant myoepithelial cells in complex and mixed tumours, both benign and malignant, there were groups of BM fragments which differed in length and thickness and occasionally formed tangles. We have called these 'membranous thickets'. Our results indicate that myoepithelial cells are the main source of the BM proteins laminin and type IV collagen in canine mammary tumours.

Adenocarcinoma↗
PubMed1995

Effect of amniotic fluid volume on ultrasonic fetal weight estimation.

We evaluated the relationship between the amniotic fluid index and the accuracy of fetal weight estimation using ultrasonography. Six hundred and sixty-four patients, between 20 and 42 weeks' gestational age, who were delivered within 1 week of a sonographic examination were studied. Five formulas for estimating fetal weight also were studied. Systematic and random errors in predicting birth weight were analyzed relative to birth weight and amniotic fluid index. The accuracy of sonographic fetal weight estimation was independent of amniotic fluid index across all gestational ages and birth weights. Each of the five formulas had similar error percentages, and no significant differences were detected. Predicted fetal weight was significantly underestimated with each of the formulas studied, a finding that was also independent of birth weight and amniotic fluid index. We conclude that ultrasonography can be used reliably to estimate fetal weight in patients with altered amniotic fluid volumes.

Amniotic Fluid↗
PubMed1995

Sleep apnea in CAPD.

Sleep disturbances are common complaints of dialysis patients, and sleep studies have suggested that sleep apnea may occur frequently. We performed sleep studies on 18 stable continuous ambulatory peritoneal dialysis (CAPD) patients. Our results indicate that 6 of 18 patients (33%) had a respiratory disturbance index (RDI) greater than 15, which indicates severe sleep apnea. Twelve of 18 patients (67%) had an RDI greater than 5, indicating clinically significant sleep apnea. These results suggest that sleep apnea is common in CAPD patients. The impact of sleep apnea on the patients' quality of life remains to be determined.

Aged↗
PubMed1995

Classical swine fever in wild boar (Sus scrofa)--experimental infections and viral persistence.

A pregnant wild boar and two wild boar weaners were inoculated intranasally with a field isolate of classical swine fever virus (CSFV) recently derived from a diseased domestic pig. The clinical, pathological and haematological findings noted in the young wild boars were comparable to those in domestic weaner pigs inoculated with the same virus isolate. Both wild boars showed the acute haemorrhagic form of CSF, one animal died 18 days post inoculation (p. i.) and the second one had to be euthanized when moribund two days later. The wild boar sow did not show any signs of illness p. i. but seroconversion was noticed. Twenty-eight days p. i. birth was given to six clinically healthy offsprings. One of the newborn proved to be viraemic until death when 39 days of age. Except for poor growth no other symptoms were noticed in this piglet. The non-viraemic litter mates remained healthy, although they had close contact to the persistently infected piglet. High titres of neutralizing antibodies against CSFV were measured in the serum samples of these offsprings. All findings were more or less in accordance with observations previously made in domestic pigs when infected with CSFV around 85 to 90 days of gestation. The wild boar was calculated to have been inoculated at about 87 to 92 days of gestation.

Animals↗
PubMed1995

[Essential fatty acids and prematurity: a triple experimental approach].

Previous studies in our laboratory have shown that in fetal plasma arachidonic (AA) and docosahexaenoic acid (DHA) levels are higher (about two fold) than in maternal plasma whereas the reverse situation was observed for the levels of their C18 precursors linoleic acid (AL) and alpha-linolenic acid (AAL) (13). This paradoxical situation raises the questions of the origin of the long chain polyunsaturated fatty acids (PUFAs) and of the ability of fetal liver to desaturate and elongate C18 precursors since placenta was shown not to be able to desaturate fatty acids. This question should be answered for the rationale of formula feeding supplementation either with long chain PUFAs or with their C18 precursors. Three experimental approaches can contribute to elucidate this dilemna: nutritional studies with formula supplementation, investigations on hepatic enzymes in vitro, in vivo experiments using stable isotopes. Supplementation of formulas with AAL in precise conditions (AL/AAL ratio: 6.4/1 and AL intake: 4.95% of total energetic supply) was done in a multicentric study including 88 premature newborns (32 weeks post conceptional age) for five weeks. The plasma phospholipid and red blood cell DHA status was found to be closer to human milk feeding than with standard formula feeding and most of the n-6 pathway was preserved. The data suggests that in premature newborns a significant conversion of AAL into DHA is possible provided an equilibrium is respected between AL and AAL supplies. This conversion is confirmed both by in vitro and in vivo studies: in fetal livers (obtained from therapeutic abortion) significant delta 6 and delta 5 desaturase activities were measured by a radiochemical method using reverse phase HPLC separation of [1-14C] labelled substrates and products in the n-6 and in the n-3 series. Substrate inhibition was observed especially at delta 5 desaturation and the maximum velocities were relatively limited mainly in the n-6 pathway which was slower than in the n-3 serie. These data are in agreement with recent preliminary data obtained in different laboratories with stable isotopes in vivo but in infants born in term: experiments using either 13C or deuterium labelled fatty acids concluded to the conversion of C18 essential fatty acids into AA and DHA justifying (AAL) formula supplementation for sustaining DHA status in preterm newborns.

Arachidonic Acid↗
PubMed1995

Expression of active human erythropoietin in the mammary gland of lactating transgenic mice and rabbits.

Transgenic mice and rabbits were generated using a chimeric gene comprising the human erythropoietin (hEPO) cDNA under the 5' and 3' regulatory sequences of the rabbit whey acidic protein gene. Transgenic mice expressed hEPO at levels of 0.01 mg/l in the milk of lactating females showing that the genetic construct was functional. Reverse transcriptase polymerase chain reaction with RNA from various tissues showed that this transgene was expressed mainly in the ovary and mammary gland. In rabbits, we demonstrated the germ line transmission of the transgene. The hEPO was obtained in the milk of lactating females at levels of up to 0.0003 mg/l. Although the expression levels were low, biologically active hEPO was obtained in the milk of transgenic rabbits without any apparent detrimental effect for the animals. In vitro, the specific activity of the rabbit-derived hEPO was higher than that reported for the natural hEPO, thus suggesting differences in the glycosylation pattern in at least part of the molecules secreted by the mammary gland of transgenic rabbits.

Animals↗